In the Western world, cases of purulent pericarditis have become almost nonexistent with progress and advent of new immunizations against many causative organisms. We report Klebsiella pneumoniae pericarditis, a rare cause of this uncommon disease, hitherto unreported in Nigeria. K. pneumoniae, which is a rod-shaped, Gram-negative, facultative anaerobe, produces extended-spectrum beta-lactamases; hence, it is usually resistant to a lot of antibiotics and is associated with a significant case fatality rate. Our 13-year-old male patient had septic arthritis of the right hip joint came with a 3 weeks complaint of difficulty with breathing. He had respiratory distress, tachypnea, and tachycardia. Although blood pressure was normal, he had pulsus paradoxus, elevated jugular venous pressure, diffuse apex beat, and heart sounds were distant. Chest radiograph revealed an increased cardiothoracic ratio (0.86) with “water bottle” appearance. Transthoracic echocardiography confirmed pericardial effusion with cardiac tamponade. Echo-guided pericardiocentesis was done, and 340 ml of foul-smelling and creamy pus with greenish tinge was aspirated and this grew K. pneumoniae sensitive to ciprofloxacin and gentamycin but resistant to other conventional antibiotics. Recovery was complete after a week of pericardial tube drainage and 3 weeks of treatment. To the best of our knowledge, this is the first case of Klebsiella - induced pyopericardium and with successful management in a Nigerian child. Pyopericardium may follow rare causes such as K. pneumoniae infection with its unique antibiogram.

Purulent pericarditis with cardiac tamponade in children, though rare, constitutes a potentially lethal disease warranting prompt recognition and aggressive management. In this condition, pus accumulates in the pericardial space as a result of infection by pyogenic organisms. Pyopericardium increases intrapericardial pressure causing the compression of all cardiac chambers, limiting cardiac inflow, and a resultant marked fall in cardiac output and culminating in cardiac tamponade which is a life-threatening condition. Without intervention, affected patients go into cardiogenic shock and death.[1] The most common causative organism for pyopericardium has been Staphylococcus aureus form both global data and the few existing reports from Nigerian.[2],[3],[4],[5] We hereby present the successful management of a rare case of purulent pericarditis with cardiac tamponade caused by Klebsiellla pneumoniae with a unique antibiogram, which has been hitherto unreported in Nigeria and highlights peculiarities of its management.

Case Report

SJ is a 13-year-old boy who was admitted to the Paediatric Emergency Unit of Aminu Kano Teaching Hospital, Kano. He had been ill for 5 weeks with complaints of the right hip pain and inability to walk and 3 weeks complaint of difficulty with breathing. At admission, he was ill looking, in respiratory distress, restless, with pressure sores on the sacral area. No fever or pallor was documented. Pertinent clinical findings were respiratory rate of 60/min, SpO2 97% in room air, radial pulse of 144/min, regular with moderate volume, blood pressure (BP) of 110/80 mmHg right arm supine, and pulsus paradoxus with a fall in inspiratory systolic BP of 12 mmHg was also present. The jugular venous pulsation was raised to the root of the neck; apex beat was diffuse, and heart sounds were distant. The liver was palpable to 8 cm below the right coastal margin and tender. He had obvious swelling around the right hip joint which was tender with differential warmth and joint held in fixed flexion position. Clinical diagnosis of septic arthritis of the right hip and pericardial effusion in heart failure was made. Plain radiographs of the right hip revealed superolateral displacement of the right femur with widening of the joint space and marked soft tissue swelling over the joint. The radiographic diagnosis was septic arthritis of the right hip with associated subluxation. High-resolution ultrasonography of the right hip showed no evidence of fluid collection, and therefore, joint aspiration was not done. Hemoglobin phenotype was AA and he was negative for retroviral screening. Chest radiograph revealed an enlarged cardiac silhouette (cardiothoracic ratio 0.86) with “water bottle” appearance [Figure 1]. Echocardiography showed large pericardial effusion (with echodense particles) with circumferential fluid accumulation, 1.2 cm separation of the pericardial layers (M-mode measurement in diastole), and anteroposterior heart swinging within the pericardial sac. Right atrial and right ventricular collapse was demonstrable on two-dimensional [Figure 2]. A diagnosis of large pericardial effusion with cardiac tamponade was made. Emergency echo-guided pericardiocentesis was done under local anesthesia by the subxiphoid approach, and 340 ml of foul-smelling and creamy pus with greenish tinge was aspirated [Figure 3]. The patient had immediate relief of respiratory distress. The cardiothoracic surgeons inserted a pericardiostomy tube for continuous drainage with over 700 ml of pus drained in 3 days. The drain was removed after 7 days. Postdrain removal, cardiac size on chest radiograph was normal. He showed remarkable improvement; no more respiratory distress, respiratory rate of 34/min (initially 60/min), and radial pulse of 108/min (initially 144/min). The culture of pus grew Klebsiella pneumoniae sensitive to ciprofloxacin and gentamicin but resistant to ceftriaxone, tetracycline, augmentin, and cotrimoxazole. The patient was initially receiving intravenous ceftriaxone 1 g 12 hourly but subsequently changed to intravenous ciprofloxacin 200 mg 12 hourly and gentamicin 40 mg 12 hourly which he received for 3 weeks following culture results. He was comanaged with the orthopedic surgeons who placed him on skin traction and was discharged in good health after 4 weeks of hospital stay. He has been followed up for 3 months and has remained clinically stable with no clinical evidence of constrictive pericarditis. He is yet to do a repeat echocardiography.{Figure 1}{Figure 2}{Figure 3}

Discussion

Purulent pericardial effusion may be associated with infection at a distant site with hematogeneous spread or a contiguous spread to the pericardium from a nearby primary site.[6],[7],[8] Our patient had septic arthritis of the right hip joint and pyopericardium would have been from hematogeneous spread. Most reported cases of purulent pericarditis have also been associated with a preexisting or concurrent infection, such as pneumonia with or without empyema, meningitis, osteomyelitis, arthritis, or other soft tissue infections. Needle aspiration is usually a temporary measure and most patients need a surgical drainage in the form of a surgical pericardial drainage tube and occasionally a pericardiectomy.

The organisms that most commonly cause purulent pericarditis are S. aureus, H influenzae, Neisseria meningitidis, and Streptococcus pneumoniae. Notably, K. pneumoniae is not a common cause of septic arthritis.[9] Infection with K. pneumoniae is a rare and serious infection in young children with predisposing underlying conditions and is associated with a significant mortality rate.[10] Yu et al. first reported a case of Klebsiella-induced pyopericardium though in an adult alcoholic patient which is not the case with our patient.[11] So far in Nigeria, Jaiyesimi et al. found that both Staphylococcus aureus and Mycobacterium tuberculosis were the most common identified pathogen (20.8% each) among 53 children with purulent pericarditis studied between 1967 and 1976 at Ibadan.[4] None was due to K. pneumoniae. In addition, Okeniyi in Ilesha reported S. aureus pericarditis as the most common infective cause of cardiac tamponade, accounting for 37.5% of cases seen over a 6 years study period with none due to K. pneumoniae.[5]K. pneumoniae, which is a rod-shaped, Gram-negative, nonmotile, lactose fermenting, facultative anaerobe, can produce extended-spectrum beta-lactamases; hence, it is usually resistant to a lot of antibiotics including aminoglycosides, fluoroquinolones, tetracyclines, chloramphenicol, and trimethoprim/sulfamethoxazole.[12] The rarity of K. pneumoniae as causative for pyopericardium and our finding of resistance to a number of commonly used antibiotics could pose significant challenge in choice of antibiotic therapy. Peculiarly, our patient was not resistant to ciprofloxacin and gentamicin.

Although the diagnosis of cardiac tamponade complicating pyopericardium may be suspected clinically in a child with the classic triad of Beck which includes distant heart sounds, distended neck veins, and hypotension; these findings are both late and inconsistent indicators of tamponade.[13] More so, fewer than 30% of patients exhibit the full triad on diagnosis.[13] Our patients did not have hypotension. The definite diagnosis is of cardiac tamponade is however made from echocardiography.[1],[14] Among echocardiographic signs, the most characteristics, although they are not entirely specific, are chamber collapses, which are nearly always of the right atrium and ventricle. During early diastole, the right ventricular free wall invaginates, and at end diastole, the right atrial wall invaginates.[15] These were evident in both cases in addition to the anteroposterior heart swinging within the pericardial sac. Echocardiography-guided pericardiocentesis, in experienced hands, is lifesaving in cases of cardiac tamponade. The therapeutic effect of pericardiocentesis largely depends on the fact that the pressure-volume relationship of the pericardium demonstrates the characteristics of hysteresis, meaning removal of a given amount of fluid diminishes intrapericardial pressure more than its addition raised the pressure.[13] In this patient, the pericardiocentesis was followed by surgical drainage. Another option now available is of instilling streptokinase through an indwelling catheter and draining the blood and mucus over 3 h and then repeating the procedure over a few days till the entire pus is drained. This can sometimes be an alternate to surgical drainage.[16]

Conclusion

This report brings to limelight the occurrence of pyopericardium following rarer causes such as K. pneumoniae infection and presents its antibiogram. Hence, physicians managing purulent pericarditis must bear this in mind as adequate antibiotic treatment will guarantee full recovery after drainage of pericardial pus. Thus, a high index of suspicion, of organisms other than S. aureus and M. tuberculosis must be borne in mind in situ ations where pus yields no growth and patient does not seem to be responding to conventional drugs for empirically targeting the aforementioned organisms.